Code signal generating device



Oct. 24, 1933. N. H. SAUNDERS CODE SIGNAL GENERATING DEVICE OriginalFiled Dec. 10, 1926 NEG J R5 R5 Q \Nw w 11+ or Nurman HEaundars 9aoJJanumoo zoo:

Patented Oct. 24, 1933 UNITED STATES 1,932,190 coma SIGNAL GENERATINGDEVICE Norman H. Saunders, Horncwood, Ill.,- assignor, bymesneassignments, to Associated Electric Laboratories, 'Inc., Chicago, 111.,a corporation of Delaware Original application December 10, 1926, SerialNo. 153,791. Patent No. 1,772,690, August 12,

. 1930. Divided and this application July 10,

1930. Serial No. 466,953

6 Claims.

erating the signalling codes required in such systems.

This application is a division of my application Serial No. 153,791,filed December 10, 1926, upon which Patent No. 1,772,690 was grantedAugust 0 12, 1930, and which discloses a party-line telephone systemembodying the invention. Only the code generating apparatus is shown inthe present application. In addition to operating with the switchingapparatus disclosed in my prior application, the invention may be usedin other known party-line telephone systems.

In automatic telephone systems, the party-line connectors and ring-backswitches are ordinarily equipped with auxiliary ringing currentselecting switches. The auxiliary switch is directively operated by acalling subscriber to select the particular code of ringing currentrequired to signal the called station, the codes used ordinarilycomprising various combinations of short and long ringing periods. Theauxiliary switch completes a circuit from the ringing relay of theconnector or ring-back switch to a code conductor which is grounded atcertain predetermined intervals by a code generating device orinterrupter. The ringingrelay operates in response to each groundimpulse and applies signalling current to the called line accordingly.

Code generating devices of the motor driven cam type and the rotarystepping switch type have been used extensively. Inasmuch as the ,codegenerator is required to operate more or less continuously during theexchange busy periods, there is considerable wear on the moving parts ofsuch devices. This necessitates frequent adjustments and replacement ofworn parts which is both troublesome and expensive. These vdiflicultiesare overcome inthe present invention which has for its main object theprovision of a novel and efiicient code generating device con-- sistingsolely of relays.

The invention will be described with reference to the accompanyingdrawing comprising Fig. 1 and Fig. 2. Fig. 1 shows the code generatingdevice. Fig. 2 indicates the codes applied to the various signalconductors 1 to 0, inclusive.

Referring now to Fig. 1 of the drawing, it will be noted that a numberof conductors terminate in circles designated 1-l0, respectively, at theright-hand edge of the sheet. These numerals indicate the particularcontact of the ringing current selecting switch bank to which theassociated code conductor is connected, i. e., conductor 1 is connectedto the first contact of the bank, conductor 2 is connected to the secondcontact of the bank, etc. It is understood, of course, thatcorresponding contacts of the various switch banks are multiplied sothat the code deviceis common to a number of connectors or ring backswitches. Conductor 375, designated Start, is multiplied to the variousswitches having access to the code device. When a switch is used toextend a call ground is applied to this conductor until the call isanswered. Conductor 376, designated Pick up, is also multiplied to thevarious connectors. This conductor is extended to the pick-up relay ofthe connector when a connection has been completed to an idle line andthe ringing code has been selected. The pick-up relay of the connectorconnects up the ringing relay of that switch so that it will respond tothe ground impulses applied to the particular code conductor selected tosignal the called station.

Relays 403 and 404 of the code generating device may be designated asthe prime-mover relays because they generate the impulsesto operate theother relays. The remaining relays, especially relays 405-410, operateto count the impulses generated by relays 403 and 404, and the device asa Whole is capable of assuming any one of nineteen positions,successively, the operation being repeated in cycles. The positions ofthe device in which the various relays are operated have been noted onthe drawing. Also the positions of the device in which the principalconductors are grounded have been noted in order that the disclosure maybe understood better.

When start conductor 375 is grounded upon the operation of theverticaloff-normal springs of an associated connector, ground is extendedthrough the lower armature of relay 402 to conductor 416, closing acircuit for relays 403 and 404, in series, through the resistanceelement 422. Relay 404 being short-circuited, relay 403 is the only onethat responds immediately. When relay 403 operates, it places ground onconductor 417 at its upper armature, and removes the shunt from aroundrelay 404 at its lower armature. Relay 404 operates and prepares toplace ground on conductor 419, and at the same time shunts relay 403.Relay 403 falls back, and the device may be said to be in its secondposition. In the second position of the device, a circuit is closedthrough the upper armaturesof relays 403 and 404 for the upper windingof relay 406, including conductor 419 and the upper armature, normal, ofrelay 405. Relay 406 operates and closes a locking circuit for itself atits upper armatureincluding the upper winding of relay 405, the lowerarmature of the said relay, and the grounded conductor 416.

With the device in position two, relay 404 is short-circuited at thelower armature of relay 403, and relay 404 shortly falls back, thedevice thereupon passing into position three. When relay 404 falls back,it removes ground from conductor 419, whereupon relay 405 operates inthe locking circuit of relay 406, and at its upper armature prepares acircuit for shunting relay 406. It will be noted now that a new lockingcircuit is completed for relays 405 and 406 in series, and that thecircuit of the upper windings of these relays is opened. The new circuitincludes the lower windings oi the relays in series and the inner lowerarmatures of the two relays.

When relay 404iallsbaclr it removesthe shunt from around relay 403 withthe result that relay l 403 operates again and removes the shunt from404' is operated in positions 1 and 2, is released momentarily, is:operated again in positions 3 and 4, etc.

the device in position 4, ground is again placed on conductor 419 shortcircuiting lower winding oi relay 406. Relay 406 falls back when thistakes place and opens the previously established locking circuit at itsinner lower armature. Relay 4'05 remains operated over conductor 419.

When the device arrives in position 5:, ground is removed from conductor419, whereupon, relay 4'05 falls back.

The above described operation of relays. 405 and 406 is repeated,beginning with position 6.

While relay 406 is operated in positions 2 and 3%, ground fromconductoris heldon impulse conductor 420, extending to the similarrelays 407 and 408. The result is an operation of relays 407- and 408'similar to the above described operation of relays 4'05 and 406 but thetime required for a complete operation is twice as: long as that ofrelays 40 5 and 406', on account of the tact that on-lyhal-i as manyimpulses are delivered over conductor 420 as are delivered overconductor 41 9. It maybe seen, therefore; that relay 408 is operated inpositions 2--5, 10-1 3-, and 18, and that relay 407 is operated inpositions 4-7, and 12-15. l g 1 ,i

It will be noted, that ground from conductor 416 is placed on conductor421 as long as relay 40'? is; operated. The result is that conductor 421is grounded in the positions of the device in which relay 407 isoperated, conductor 421 being the impulse conductor extending to thethird pair of counting relays 409 and 410. It maybe seen, therefore,that, relay 410 is operated in positions 4,-1'1, and that relay 409 isoperated in positions 8'1'5. f When conductor 418 is grounded inposition 2, a circuit is closed through the lower arma ture of relay412' for relay, 413. Relay 413 operates and locks itself through themiddle lower armature of relay 412 to conductor 16, and re mainsoperated until relay 412 operates in position 13, as will be pointed outhereinafter.

When the device arrives in position 6, relay 414 is operated from thegrounded conductor 416 through the inner lower armature of relay 407,lower armature of relay 406, and the lower armature of relay 413. Relay414 operates and locks itself through the locking conductor of relay413, with the result that relay 414 remains operated unti'l'ground isremoved from this locking concluster at. the beginning of position 13when relay 412 operates.

When the device arrives in position 12, a circuit for relays 411 and 401in series is completed from conductor 416 through the inner lowerarmature of relay 405,. inner lower armature, normal, of relay 406,middle upper armature of relay 408, and the middle upper armature ofrelay 409. At its lower armature relay 411 looks itself and relay 401 toconductor 416 Relay 401 prepares a locking circuit for relay 402 at itsinner armature.

When the device arrives 405 falls back and closes at its lower: armaturea circuit through the inner upper armature of 411 for relay 412.v Relay41 23 operates and locks itself to conductor 416' until conductor 416 isungroun'ded in position 18. At its middle lower armature, relay 412opens the lo'cking'ci rcuit of relays 413 and 414, whereupon theserelaysfall back.

Whenthe. device arrives in position 18, relay 408 is operated again, anditv completesfat' its upper armature a circuit for relay 402: includingthe upper armature of relay-412and the middle lower armature of relay409... Relay 402,. thereupon operates and locks. itself to conductor3'15 through the inner armature of relay 401,. at the same time openingits initial circuit. At its, lower armature, relay 402 removesgrou-nd'froni con+ ductor 416. and places ground on pick-upcomductor376.. The removal ofground from conductor 41'6. stops. the. operationofrelays 403 and 404 and permitsthe operated relay .404 -to fall back, andv it opens. the locking circuits: oi the relays. 4054-414, permittingsuch of these: relays as are operated to fall back. Relay 40.1,. whichis in series. with relay 411, is slow-acting and does not i all backright away when its circuit is opened upon the removal of ground from;conductor 4116i When relay 401 falls back it opens-the locking circuitof relay 402, the device is in position. 19.

position-'13, relay fro ifs

fro

A. moment later relay 402' falls back and removes to terminal 1 isgrounded through the lower armatures of relays 401 and 408' while thedevice is in positions 25,; this code corresponds toone long ring. a

The conductor extending to terminal 2 is grounded through the upperarmatures of relays 403 and 411, and the middle armature of relay 410while the device is in positions 1 and 3; this code corresponds to twoshort rings.

The conductor extending to terminal 3 is grounded in. positions 3, 5,and 7 of the device through the upper armatures of relays 411, 413, and409; this code corresponds to three short rings.

The conductor extending to terminal 4 is connected to the impulseconductor 417 through the upper armature of relay 411 and the middleupper armature of relay 410, and is grounded in positions 5, '7, 9, and11; this, code corresponds to four short rings.

In a similar way, the remainingcode conductors are grounded in thepositions indicated. The code placed on the conductor extending toterminal 5 corresponds to five short rings; the code placed on conductor6 corresponds to two long rings; the code placed on conductor 7corresponds to three long rings; the code placed on conductor 3corresponds to a short ring and a long ring; the code placed onconductor 9 corresponds to a short ring and two long rings; and the codeplaced on conductor 10 corresponds to two short rings and two longrings.

What is claimed is:

1. In combination, a device iorgenerating impulses, a relay group, meansfor operating certain relays of said group in response to said impulsesthrough a certain cycle at a definite rate, means for operating certainother of said relays through a similar cycle of operations at a ratehalf that of the first mentioned relays, and auxiliary relays controlledby the first and second mentioned relays for operating the entire relaygroup in cycles, each of the latter cycles including a plurality ofcycles of the first and second mentioned relays, circuit connectionsincluding code conductors and contacts controlled by said relays forgenerating a plurality of different code signals.

2. In combination, a device for generating uniform impulses at adefinite rate, groups of relays, means for operating the first relaygroup in response to said impulses through a certain cycle of operationsat a definite rate, means for operating the second relay group through asimilar cycle of operations at one half the rate of the first relaygroup, means for operating the third relay group through a similar cycleof operations at one half the rate of the second relay group, meanscontrolled by said relay groups jointly for generating long and shortimpulses, and means for combining said long and short impulses into aplurality of different signal codes.

3. A code signal generating device comprising a plurality of signalconductors, a device for generating a series of uniform short impulses,a group of relays, circuit connections between said device and saidrelays for operating and releasing the relays to transform said shortimpulses into code signals comprising groups of long and short impulses,and contacts operated by said relays to impress said code signals uponsaid signal conductors. v

4.. A code signal generating device comp-rising a plurality of signalconductors, a plurality of relays, means for operating and releasingcertain of said relays at a predetermined rate, means for operating andreleasing certain other of said relays at a different predeterminedrate, and means responsive to the operation and release of said relaysfor transmitting code signals over said signal conductors.

5. A code signal generating device comprising a plurality of pairs ofrelays, means for operating the first relay pair through cyclesconsisting of the successive actuation and successive release of therelays, means for operating the second relay pair through a similarcycle responsive to the operation of the first relay pair through twocomplete cycles, means controlled by said relay pairs for generatinglong and short impulses, and. means controlled by said relay pairs forcombining said impulses in a plurality of different combinationsrepresenting code signals.

6. A code signal generating device comprising a plurality of pairs ofrelays, means for operating the first relay pair at a definite ratethrough cycles consisting of the successive actuation and successiverelease of the relays, means for operating successive relay pairsthrough similar cycles at a rate one half that of the rate at which therelay pair immediately preceding is operated, a plurality of signalconductors, and means controlled loy said relays for transmittingseparate and distinct codes of impulses over the respective ones of saidconductors.

NORIVIAN H. SAUNDERS.

